Blue Peter has become the latest television programme to become embroiled in the premium-rate phone-line scandal after it emerged the show faked the winner of a viewer competition after the phone lines failed.

The BBC1 children's show ran a phone-in competition to raise money for its Blue Peter Appeal in aid of Unicef.

But a technical failure meant the production team was unable to access viewer calls, and a member of staff asked a child visiting the studio to phone the programme and give the answer on air. She was then awarded the prize.

The BBC Children's controller, Richard Deverell, admitted the decision to put the child on air was a "serious error of judgment".

"I would like to apologise unequivocally to viewers, to all the children who took part in the competition, and we have already apologised directly to the child involved and her family for this incident."

The corporation said an apology will be broadcast to viewers in today's edition of the show. It has launched an immediate review of all live competitions on Children's BBC, and set up a freephone number - 08000 565 363 - for viewers who took part in the competition and want more information.

Jana Bennett, the director of BBC Vision, has announced a "senior level independent review" and described it as a "serious breach of editorial standards".

The Blue Peter editor, Richard Marson, said the programme "fell short of the high standards Blue Peter viewers quite rightly expect. We are absolutely committed to running competitions that are fair to all entrants and we are very sorry for the way this competition was conducted."

The incident was revealed after a viewer emailed the BBC last Friday about the competition, which ran on November 27.

The competition was part of the annual Blue Peter appeal, which was raising money for Unicef. Viewers paid 10p to call the programme - with 3.25p going to Unicef - for the chance to win a prize from a list of children's toys.

In a statement, the BBC said there was a "technical failure" during the live programme which meant that "calls were being received correctly by the telecoms operator" but "studio staff were having difficulty retrieving the information as originally planned".

"This meant that a caller was not selected to give their answer on air, as was promised at the beginning of the programme. A member of staff then asked a child, who was visiting the studio, to phone in to the programme and to give an answer on air. The child was awarded the prize."

Mr Deverell said: "BBC Children's has a deep and genuine commitment to our audiences, and our relationship with them is built on trust.

"Whilst I am satisfied that there was no premeditated attempt to deceive or mislead viewers, the decision to put a child on air in this way was a serious error of judgment, and does not conform to either the BBC's own guidelines or the high standards we set ourselves in Children's programmes.

"I would like to apologise unequivocally to viewers, to all the children who took part in the competition, and we have already apologised directly to the child involved and her family for this incident. Part of our commitment to a relationship built on trust requires us to disclose this error and try to put it right, which we are now doing. It is very important that Blue Peter takes action to do this, and to ensure that lessons are learned."

A new winner will be randomly selected from the original competition entrants in a process overseen by an independent solicitor to verify the process to premium phone-line regulator, Icstis. The senior level independent review will be conducted by Andrea Willis, a former chief adviser, BBC editorial policy.

Ms Bennett said: "Blue Peter enjoys the highest reputation for its relationship of trust and respect for the audience. It is disappointing, therefore, that there has been a serious breach of editorial standards on a live edition of the programme.

"I believe the action that is being taken by BBC Children's will help to reassure children and parents that we take this matter very seriously indeed.

"I have, however, invited Andrea Wills to conduct an immediate and independent review of the incident, the actions taken, and the lessons to be learned from it, which will report directly to me. This will help to inform the wider review of the use of programmes which use premium-rate lines which is already under way."

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